Speech discrimination in automated diagnostic hearing test

ABSTRACT

Method and system are disclosed for automated testing of a patient&#39;s hearing. The automated hearing test allows the patient to quickly and accurately test his own hearing with minimal or no assistance from an audiologist or other hearing health professionals. The test prompts and instructs the patient for inputs and responses as needed as needed. The patient can select one or several tests to be performed, including air and bone conduction testing with masking, speech reception threshold, speech discrimination, and tympanogram/acoustic reflex testing. Multiple languages are supported. Data obtained from one test may be used for another test or another iteration of the same test to calculate masking levels. The automatic hearing test also detects ambient noise and can compensate for it in the test results. If a contingency occurs, the automated hearing test is configured to page the operator for assistance.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application for patent claims the benefit of priority from,and hereby incorporates by reference, U.S. Provisional PatentApplication Serial No. 60/383,303, entitled “Audiometer” and filed onMay 23, 2002, and U.S. Provisional Patent Application entitled “Systemand Method for Conducting Multiple Diagnostic Hearing Tests,” filed onApr. 29, 2003.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] This invention is directed in general to the field of audiologyand in particular to an automated method and system for assessment andanalysis of hearing loss.

[0004] 2. Description of the Related Art

[0005] According to recent studies, over 20 million people in the UnitedStates alone have some degree of hearing loss. The number of peopleworldwide who have some degree of hearing loss is estimated to be muchgreater. Not surprisingly, many of these people are unaware that theyhave suffered a decrease in hearing capacity. The decreased hearingcapacity may be due to several factors, including age, health,occupation, injury, and disease. This loss of hearing can lead tosignificant reductions in quality of life, impaired relationships,reduced access to employment and diminished productivity. Failure totreat the hearing loss may worsen the impact. According to the BetterHearing Institute, the annual cost in the United States in terms of lostproductivity, special education, and medical care because of untreatedhearing loss is approximately $56 billion. Much of this staggering costcan be reduced or prevented by early detection and treatment,Unfortunately, few people obtain regular and frequent hearing tests as apart of their routine healthcare due, in part, to the lack of a simple,convenient, and relatively inexpensive hearing test.

[0006] Traditionally, a hearing test is conducted in a clinical settingby a hearing health professional, such as an audiologist, whoadministers the hearing test manually. The hearing health professionalcontrols an audiometer to produce a series of tones that each have avery specific frequency and intensity. The term “intensity” as usedherein refers to the amplitude of the tone and is usually stated indecibels (dB). The tones are then conducted through a transducer, suchas earphones or ear inserts, to the patient in a quiet room or soundisolation booth. For each audible tone, the patient gestures orotherwise indicates that he has heard the tone. If the tone is notaudible, the patient does not respond. The hearing health professionalthereafter adjusts the intensity level of the tone in preset incrementsuntil it becomes audible to the patient. By repeating this process forseveral different tones and compiling the results, the hearing healthprofessional is able to determine the extent of the hearing loss, ifany.

[0007] An advantage of having a hearing health professional manuallyadminister the hearing test is the hearing health professional can applyhis considerable training and experience during the test. For example,by simply talking to the patient and varying the loudness of his voice,the hearing health professional can determine an initial intensity levelat which to start the tones and sounds. Furthermore, the hearing healthprofessional can adapt the pace of the test as needed to accommodate atired or uncooperative patient. More importantly, the hearing healthprofessional can discern between false responses or guesses andresponses that are legitimate. Finally, the hearing health professionalcan adjust the results of the hearing test as needed to reflectextenuating circumstances or problems, such as excessive ambient noise,equipment limitations, and other similar factors.

[0008] Like most highly trained and specialized medical professionals,however, a hearing health professional's time and services are usuallyvery expensive. Accessibility and convenience can also be issues, asthere are fewer hearing health professionals relative to other types ofmedical professionals. And while hearing health professionals are highlytrained, they are limited in their ability to make rapid and accuratecalculations of the test data and have to rely on approximations andrules of thumb for guidance in many instances. In addition, few hearinghealth professionals in the United States can speak a foreign language.As a result, traditional hearing tests are almost always administered inEnglish, which can be a problem for non-English speaking patients.

[0009] Other drawbacks of the traditional, manually administered hearingtests include the need for a quiet room or sound isolation booth inorder to properly conduct the tests. The quiet room or sound isolationbooth has to comply with ANSI (American National Standards Institute)requirements in terms of how much noise may penetrate the room or boothduring a test. Typically, a specially trained technician must evaluateand certify the quiet room or sound isolation booth as meeting ANSIstandards before the room or booth can be used. At present, there arerelatively few technicians who are trained to perform such evaluationsand certifications. All the above factors combine to increase thecomplexity of the traditional hearing tests and thereby discourage or atleast contribute to a general lack of interest by most people inobtaining regular and frequent hearing tests.

[0010] One attempt to simplify the traditional hearing test involves theuse of a computer network, such as the Internet, to administer the test.The computer network facilitates interaction between a centralized testadministration site and remotely located patient sites. Such anarrangement makes it possible (or at least more convenient) for peoplein remote or rural areas to obtain a hearing test. And the hearing testcan be performed so that it meets standardized guidelines such as ANSIrequirements or certification standards. Despite the increasedconvenience, a hearing health professional must still manuallyadminister the test, albeit remotely. In this regard, the test is verysimilar to the traditional hearing test and has many of the sameshortcomings.

[0011] Accordingly, what is needed is a hearing test that overcomes theshortcomings of the traditional hearing test. Specifically, what isneeded is a hearing test that is simpler, more convenient, lessexpensive, can be administered by the patient rather than by the hearinghealth professional, yet does not compromise the accuracy orthoroughness of the traditional, manually administered hearing test.

SUMMARY OF THE INVENTION

[0012] The present invention is directed to a method and system forautomated testing of a patient's hearing. The automated hearing testallows the patient to quickly and accurately test his own hearing withminimal or no assistance from an audiologist or other hearing healthprofessionals. The test prompts and instructs the patient for inputs andresponses as needed as needed. The patient can select one or severaltests to be performed, including air and bone conduction testing withmasking, speech reception threshold, speech discrimination, andtympanogram/acoustic reflex testing. Multiple languages are supported.Data obtained from one test may be used for another test or anotheriteration of the same test to calculate masking levels. The automatichearing test also detects ambient noise and can compensate for it in thetest results. If a contingency occurs, the automated hearing test isconfigured to page the operator for assistance.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] A better understanding of the invention may be had by referenceto the following detailed description when taken in conjunction with theaccompanying drawings, wherein:

[0014]FIG. 1 illustrates an exemplary system for providing an automatedhearing test according to embodiments of the invention;

[0015]FIG. 2 illustrates a block diagram of the system for providing anautomated hearing test according to embodiments of the invention;

[0016]FIG. 3 illustrates the exemplary functional components of theautomated hearing test according to embodiments of the invention;

[0017]FIG. 4 illustrates an exemplary flowchart for a main programmodule according to embodiments of the invention;

[0018]FIG. 5 illustrates an exemplary flowchart for a pure tonefrequency module according to embodiments of the invention;

[0019]FIG. 6 illustrates an exemplary flowchart for a pure tonethreshold module according to embodiments of the invention;

[0020]FIG. 7 illustrates an exemplary flowchart for a pure toneintensity module according to embodiments of the invention;

[0021]FIG. 8 illustrates an exemplary flowchart for a pure tone initialintensity module according to embodiments of the invention;

[0022]FIG. 9 illustrates an exemplary flowchart for a set pure tonemasking levels module according to embodiments of the invention;

[0023]FIG. 10 illustrates an exemplary flowchart for a thresholddetection module according to embodiments of the invention;

[0024]FIG. 11 illustrates an exemplary flowchart for a speech receptionthreshold module according to embodiments of the invention;

[0025]FIG. 12 illustrates an exemplary flowchart for a set speechmasking levels module according to embodiments of the invention;

[0026]FIG. 13 illustrates an exemplary flowchart for a speechdiscrimination module according to embodiments of the invention; and

[0027]FIG. 14 illustrates an exemplary flowchart for a patientmanagement module according to embodiments of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0028] Following is a detailed description of the invention withreference to the drawings wherein reference numerals for the same orsimilar elements are carried forward.

[0029] As mentioned above, the present invention is directed to a methodand system for automated testing of a patient's hearing. The term“automated testing” as used herein refers to testing that is performedprimarily by a computer, as opposed to testing that is performedprimarily by a hearing health professional. The automated hearing testallows the patient to test his own hearing with minimal or no assistancefrom an audiologist or other hearing health professional. Typically, anoperator, such as the hearing health professional or a trainedassistant, helps the patient with the initial set up (e.g., seating,putting on the headset, demonstrating button usage, etc.) and explainshow the test works. Thereafter, the automated hearing test prompts andinstructs the patient for all inputs and responses needed. If acontingency occurs, for example, the patient falls asleep, the automatedhearing test alerts (e.g., by paging) the operator as needed. Such apatient-administered hearing test can be simpler, more convenient, andless expensive than the traditional, audiologist-administered test.

[0030] In addition, the hearing test of the present invention providesan accurate and thorough assessment of the patient's hearing. Theautomated hearing test includes air and bone conduction testing withmasking, speech reception threshold testing, speech discriminationtesting, and can accommodate tympanogram, acoustic reflex, otoacousticemission, and acoustic immitance testing. The tests are performed in amanner to comply with relevant standards and guidelines such as ANSIrequirements and other standards. Furthermore, the automated hearingtest can detect and compensate for ambient noise and, therefore, doesnot require the use of a certified quiet room or sound isolation booth.Finally, the automated hearing test can be configured for any number oflanguages for patients in all parts of the world.

[0031] Hearing health professionals will also benefit from the automatedhearing test of the present invention. Although the test itself requireslittle or no intervention, a hearing health professional still mustanalyze the test results and recommend treatment. Therefore, theautomated hearing test is, at least initially, made available onlythrough a qualified hearing health professional. The hearing healthprofessional may offer the automated hearing test as a separate serviceor as part of a more comprehensive service, such as a full physicalcheckup that patients can obtain annually. Since the test requireslittle or no intervention, the hearing health professional does not haveto spend much time administering the test. As a result, he will havemore time for each patient and/or be able to treat more patients.Moreover, since the automated hearing test facilitates early detectionof hearing loss, the treatment needed may be less severe than if thehearing loss had been detected later.

[0032] Referring now to FIG. 1, a system 100 for providing automatedhearing tests according to some embodiments of the invention is shown.The system 100 has three main components, namely, a computer 102, and adisplay screen 104, and at least one transducer 106. Other components ofthe system 100 that may be present include a tympanometer, keyboard,mouse, printer, paging system, and the like (indicated generally at108). The paging system may be any suitable paging technology that usesone or more pagers or other wireless mobile devices 108 for alerting theoperator. The mobile terminal 108 preferably can display text messagesfor informing the operator of the nature of the alert. Other types ofpaging system may also be used without departing from the scope of theinvention (e.g., wired paging systems).

[0033] The computer 102 may be any suitable computer, from a desktop PCto a high-end workstation, as the particular type/model/brand ofcomputer is not overly important to the practice of the invention. Thedisplay screen 104 may likewise be any suitable display screen, from aCRT to an LCD, as the particular type/model/brand of display screen isnot overly significant for purposes of the present invention. In someembodiments, however, a touchscreen monitor may be easier to use thanconventional CRT for LCD display screens in terms of the physicalinteraction between the patient and the automated hearing test.

[0034] As for the transducer 106, this component may be an ear insert,earphones, and the like for air conduction. For bone conduction, thetransducer 106 may be a vibrator or other similar devices. In somecases, the transducer 106 may be mounted on a headset worn by thepatient. Usually, a separate transducer is used for air conductionversus bone conduction and the transducers are swapped as need duringthe hearing test. Preferably, the bone conduction transducer is arrangedin such a way as to allow testing of either ear without moving thetransducer and without interfering with the air conduction transducer.In some embodiments, both the air conduction transducer and the boneconduction transducer are combined in a single unit. An example of sucha combined unit is described in U.S. Provisional Patent Applicationentitled “System and Method for Conducting Multiple Diagnostic HearingTests,” filed on Apr. 29, 2003, which is incorporated herein byreference.

[0035]FIG. 2 illustrates the system 100 in block diagram form. As can beseen, the computer 102 has a number of functional components, includinga video unit 200, a central processing unit 202, a hearing test device204, and a storage unit 206. These components are well known in thecomputer art and will therefore be described only briefly here. Ingeneral, the video unit 200 provides the video signals that aredisplayed as images on the display screen 104. In some embodiments, thevideo unit 200 may be any one of several commercially available videocards. The central processing unit 202 is responsible for the overalloperation of the computer 102, including execution of the operatingsystem and any software applications residing on the computer 102. Insome embodiments, the central processing unit 202 may be any one ofseveral commercially available microprocessors. The hearing test device204 may comprise any or all of an audiometer, an otoacoustic emissiontest device, a tympanometer, a masking noise generator, or other hearingtest devices. In some embodiments, the hearing test device 204 may beone or more electronic circuit boards within the computer 102 forperforming the functionality of such test devices. Alternatively, thehearing test device 204 may be a separate unit that is external to thecomputer 102. The storage unit 206 provides long-term and temporary(i.e., caching) storage for the software and data that are used by thecomputer 102 and may include one or more of, for example, a hard drive,main memory, removable storage (e.g., CD-ROM, floppy disk), and thelike.

[0036] In some embodiments, the storage unit 206 also stores theautomated hearing test of the present invention, indicated at 208. Morespecifically, the storage unit 206 stores a computer-readable version ofthe automated hearing test 208 that can be executed by the computer 102.During execution, a portion of the automated hearing test 208 may betemporarily loaded from, for example, the hard disk and into the mainmemory components of the storage unit 206. In addition to thestand-alone arrangement, it is also to possible to execute the automatedhearing test 208 from a network. For example, the automated hearing test208 may be stored on a server computer (not expressly shown) that isaccessible to several client computers. This arrangement has anadvantage in that updates to the automated hearing test 208 may bequickly and easily implemented. Other environments for executing theautomated hearing test 208 may also be used without departing from thescope of the invention.

[0037] The source code for the automated hearing test 208 may be writtenin any suitable programming language (e.g., C, C++, BASIC, Java). It hasbeen found, however, that object oriented programming languages such asC++, Visual Basic and Java can result in a somewhat more efficientprogram. In addition, the automated hearing test 208 can be implementedusing a number of different programming methodology (e.g., top-down,object oriented). The particular programming methodology as well as theparticular programming language used are not overly importantconsiderations for the practice of the invention. In one embodiment, themethodology of the automated hearing test 208 involves a plurality ofindividual modules or object class modules with subroutines, propertiesand functions that can be called to perform specific tasks. The modulesor subroutines can be called from a main routine and from within othermodules or subroutines. The subroutines can pass data to and from eachother as well as to and from the main routine. FIG. 3 shows an exampleof this particular embodiment of the automated hearing test 208.

[0038] As can be seen in FIG. 3, the automated hearing test 208 includesa main program module 300 and a plurality of individual subroutines orclass modules, including a pure tone frequency module 302, and a puretone threshold module 304. A pure tone intensity module 306, a pure toneinitial intensity determination module 308, and a pure tone maskinglevels module 310 are also present. Other modules include a thresholddetection module 312, a speech reception threshold module 314, a speechmasking levels module 316, a speech discrimination module 318, and apatent management module 320. In evaluating the various modules, itshould be emphasized that this particular combination of modules isexemplary only, and that one or more modules may be omitted or othermodules may be added as needed. Furthermore, two or more modules may becombined into a single module, or a single module divided into severalsub-modules as needed.

[0039] Functionally, the main program module controls the generalsequence or flow of the hearing test 208. When specific functions ortasks need to be performed, the main program module calls theappropriate modules to perform the needed functions or tasks. Forexample, the main program module calls the pure tone frequency module inorder to test the patient's ability to hear pure tone frequencies.Similarly, the speech reception threshold module is called in order totest the patient's ability to hear speech, and the speech discriminationmodule is called in order to test the patient's ability to discriminatebetween similar sounding words.

[0040] Each of the modules can also call other modules when specificfunctions or tasks need to be performed. For example, while the puretone frequency module controls which pure tone frequencies will betested and in what sequence, the actual threshold testing is performedby one or several other modules. Thus, after being called by the mainprogram module, the pure tone frequency module can call, for example,the pure tone intensity module in order to obtain the patient'sthreshold intensity for a given frequency. The pure tone intensitymodule, in turn, calls the pure tone initial intensity determinationmodule in order to determine the initial intensity level at which tobegin testing. The pure tone intensity module also calls the pure tonemasking levels module in order to determine the amount of masking thatshould be used with a given frequency. Finally, the pure tone intensitymodule calls the threshold detection module in order to establishwhether a threshold intensity has been reached. The threshold detectionmodule can also be called by the speech reception threshold module forthe same purpose. The speech reception threshold module further callsthe speech masking levels module in order to determine the amount ofmasking to be used during the speech reception threshold test. FIGS.4-13 illustrate one exemplary implementation out of several possibleimplementations for each of the modules 302-320.

[0041] A key design feature of the automated hearing test is the abilityto share data between all the modules that are called. For example, dataacquired by the pure tone frequency module during the pure tonefrequency test may be shared with the speech reception threshold moduleduring the speech reception threshold test. Similarly, data acquiredduring one iteration of a module may be shared with another iteration ofthe same module. This type of data sharing arrangement results in a moreefficient and more accurate test overall. Where no data exists to beshared, the modules may use rules of thumb type data or best-guest typedata.

[0042] Referring now to FIG. 4, a flowchart 400 illustrates theoperation of the main program module according to some embodiments ofthe invention. As mentioned above, the main program module controls thegeneral sequence or flow of the automated hearing test 208. The mainprogram module allows the patient to select which tests are to beperformed, then controls when and how various subroutines or modules arecalled to carry out the selected tests. After initial power up, the mainprogram module performs an equipment check at step 401 to ensure allcomponents (e.g., transducers, audiometer, etc.) of the system arefunctioning properly. Such a check may involve, for example, comparingthe initial calibration data of the equipment with current measurements.In some embodiments, the various components of the equipment may bepre-calibrated together as a unit during manufacture or assembly. Thecalibration data may then be stored in a storage medium that isconnected or attached to or sent together with the equipment. Adetermination is made at step 402 as to whether the equipment checkpassed, that is, whether the equipment is within a predeterminedpercentage of the initial calibration data. If the equipment checkfails, then the main program module issues an equipment failure warningand returns to the first step 401 to re-check the equipment.

[0043] If the equipment check passes, then the main program moduleproceeds to obtain the patient's information at step 404. This can bedone, for example, by prompting the patient to manually enter hisinformation (e.g., name, address, date of birth, etc.), or by loadingthe information from a previously stored patient file. Here, asthroughout the description, manual prompting may be done visually bydisplaying the instructions as text on the display screen 104, or byaudio instructions via the transducer 106, or by a combination of bothin a multimedia approach. At step 405, the main program module obtainsthe patient's preferred language (e.g., English, Spanish, French, etc.),again, by prompting the patient, or by loading the selection from apreviously stored file. At step 406, the main program module allows thepatient to select one of several tests to be performed, including atympanogram/acoustic reflex test, a pure tone test, a speech receptionthreshold test, and a speech discrimination test.

[0044] After the above selection, the main program module makes adetermination as to whether the tympanogram/acoustic reflex test wasselected at step 407. The purpose of this test is to check the acousticadmittance of the ear and is usually conducted by an operator of atympanometer (indicated generally at 108). The tympanometer may be anysuitable tympanometer that can be connected to and communicate with thecomputer 102. Most commercially available tympanometers have a serial,parallel, or other data port that can be used to transfer data to andfrom the computer 102. If the tympanogram/acoustic reflex test wasselected, then at step 408, the main program module presents theoperator with the left ear instructions (e.g., insert tympanometer,start test). At step 409, the main program module obtains the left eardata from the tympanometer. The main program module thereafter promptsthe operator at step 410 to indicate whether the data is acceptable. Ifthe operator indicates the data is not acceptable, the main programmodule asks the operator at step 411 whether to keep trying to obtain atympanogram for the left ear. If the operator decides to keep trying,then the main program module repeats the process for the left earstarting at step 408. On the other hand, if the operator decides not tokeep trying, or that the data is acceptable, then the main programmodule runs through the same process for the right ear at steps 412,413, 414, and 415.

[0045] In some embodiments, instead of the operator performing thetympanogram/acoustic reflex test, the automated hearing test 208 maycontrol the tympanometer so that the test is performed automatically. Inthese embodiments, the tympanometer may be a separate unit, or it may bea part of the functionality provided by the hearing test device 204. Themain program module may then be configured to provide instructions tothe patient on how to insert the probes for the tympanogram/acousticreflex test. The probes may be standard probes used for such tests, orthey be combination probes similar to the one described in U.S.Provisional Patent Application entitled “System and Method forConducting Multiple Diagnostic Hearing Tests,” mentioned above. The mainprogram module then controls the operation of the tympanometer toinitiate the test and acquires the resulting data. A similar arrangementmay be used for other hearing related tests.

[0046] If the tympanogram/acoustic reflex test was not selected step407, then the main program module proceeds to step 416, where it checkswhether the pure tone test was selected. The purpose of this test is toassess what loss has occurred in the patient's ability to hear puretones (e.g., a single frequency or a very narrow band of frequencies).The data obtained during the pure tone frequency test can then be usedfor the other tests. If the pure tone test was not selected, the programmodule proceeds to step 419. If the pure tone test was selected, themain program module thereafter presents instructions to the patient atstep 417 on how to perform the test (e.g., what to expect, when torespond, how to respond, etc.). At step 418, the main program modulecalls the pure tone frequency module to perform the pure tone test, thedetails of which will be described below. The main program modulethereafter proceeds to step 419 for the speech reception threshold test.

[0047] At step 419, a determination is made as to whether the speechreception threshold tests was selected. The purpose of this test is toassess what loss has occurred in the patient's ability to hear speech.If the speech reception threshold test was not selected, then the mainprogram module proceeds directly to step 422 for the speechdiscrimination test. If the speech reception threshold test wasselected, then the main program module presents instructions to thepatient on how to perform the test at step 420 (e.g., what to expect,when to respond, how to respond, etc.). The main program modulethereafter calls the speech reception threshold module to perform thespeech reception threshold tests at step 421, the details of which willbe described below. The main program module then proceeds to step 422for the speech discrimination test.

[0048] At step 422, a determination is made as to whether the speechdiscrimination test was selected. The purpose of this test is to assesswhat loss has occurred in the patient's ability to discriminate betweensimilar sounding words. If the speech discrimination test was notselected, then the main program module proceeds directly to step 425 toconclude the test session. Otherwise, the main program module presentsinstructions to the patient on how to perform the test at step 423(e.g., what to expect, when to respond, how to respond, etc.). The mainprogram module thereafter performs the speech discrimination tests atstep 424, the details of which, again, will be described with respect toFIG. 4 below. The main program module then proceeds to step 425 toconclude the test session.

[0049] At step 425, the main program module alerts the operator that thepatient has completed his hearing test, for example, by causing theoperator to be paged. In some embodiments, the main program module alsopages the operator if the patient does not complete the hearing testwithin a reasonable amount of time, for example, one hour. If thepatient has not completed the hearing test within the given time, thenthat may indicate the patient is having some difficulty progressingthrough the test. The operator may also be paged by the patient, forexample, by pressing an onscreen button if he needs assistance. Oncecompleted, the main program module saves the data acquired from thetest, for example, by storing the data onto a disk of the storage unit206 at step 426. At step 427, the main program module generates andprints a standardized report based on the test data from the justconcluded test session.

[0050] At step 428, the main program module offers the operator a numberof options, including the option to view the results, repeat the test,begin a new session, print the test data, and archive the results. Themain program module thereafter waits for the operator to make aselection. If the operator chooses to view the results, the main programmodule displays the test data on the display screen 104, and returns tothe previous step. If the operator chooses to rerun the hearing test,the main program module returns to step 406 and prompts the operator toselect the tests to be rerun. If, on the other hand, the operatorchooses to begin a brand new session, the main program module returns tothe very first step 401. If the operator chooses to print the testresults, then the main program module returns to step 427 and prints theresults. If the operator chooses to archive the results, then the mainprogram module returns to step 426 and saves the result to disk.

[0051] Referring now to FIG. 5, a flowchart 500 illustrates an exemplaryimplementation of the pure tone frequency module according toembodiments of the invention. The pure tone frequency module controlswhich pure tone frequencies are tested and in which sequence. As will bedescribed below, a key design feature of the pure tone frequency moduleis its ability to determine whether certain frequencies need to betested and to bypass the ones that do not need testing. This type offrequency selection process is very similar to the process that ahearing health professional would go through during a manuallyadministered test and can result in a shorter and more efficient testoverall.

[0052] At the first step 501, the pure tone frequency module obtains thethreshold intensity for the first pure tone, which is about 1000 Hz inthis embodiment. The threshold intensity is defined as the lowestintensity, rounded to the nearest 5 dB, at which the tone is audible tothe patient at least 50% of the time. The pure tone frequency moduleobtains the threshold intensity by calling the pure tone thresholdmodule and passing to it the frequency to be tested. The pure tonethreshold module performs the pure tone threshold test (described below)and returns the results to the pure tone frequency module. At the secondstep 502, the pure tone frequency module obtains the threshold intensityfor the second pure tone, which is about 500 Hz in this embodiment, byagain calling the pure tone threshold module and passing the second puretone information to it.

[0053] At the next step 503, the pure tone frequency module determineswhether it needs to test below the 500 Hz level. This step is anoptional step that is intended to reduce test time by skipping the lowerfrequencies if the results of lower frequency testing would notsignificantly add to the diagnostic information included in the hearingtest report. The pure tone frequency module makes the determination bycomparing the patient's threshold intensity at 500 Hz to the minimumsignificant 500 Hz threshold. The minimum significant 500 Hz threshold,according to some audiologists, is between 10 dB and 30 dB. If thepatient's threshold intensity at 500 Hz is greater than or equal to theminimum significant 500 Hz threshold, then the pure tone frequencymodule proceeds to obtain the threshold intensity at a lower frequency,which is about 250 Hz in this embodiment. If the patient's 500 Hzthreshold intensity is less than the minimum significant 500 Hzthreshold, then there is less of a need to test at lower frequencies andtime can be saved by skipping these frequencies. This demonstrates theadvantage of starting the pure tone test at 1000 Hz rather than at thelowest frequency in the audible spectrum, since it is not alwaysnecessary to tests at the lowest frequencies. In some embodiments,however, the pure tone frequency module may test the lower frequenciesanyway, or it may start at the lowest frequency in order to be asthorough as possible.

[0054] Next, the pure tone frequency module proceeds to obtain thethreshold intensity at, for example, 2000 Hz (step 505) and at 4000 Hz(step 506), by again calling the pure tone threshold module and passingthe frequency information to it. The pure tone frequency module maythereafter implement another optional time-saving measure at step 507 bydetermining whether the difference between the 2000 Hz and 4000 Hzthresholds is greater than a minimum significant interoctave difference.This minimum significant interoctave difference is considered by someaudiologist to be about 20 dB. If the difference between the 2000 Hz and4000 Hz thresholds is greater than or equal to the minimum significantinteroctave difference, then the pure tone frequency module proceeds atstep 508 to obtain the threshold intensity at 3000 Hz. Otherwise, thepure tone frequency module proceeds to step 509 to obtain the thresholdintensity at, for example, 8000 Hz. At this point, the pure tonefrequency module may implement another optional time-saving measure atstep 510 by determining whether the difference between the 4000 Hz and8000 Hz thresholds is greater than or equal to the minimum significantinteroctave difference. If it is, then the pure tone frequency moduleproceeds at step 511 to obtain the threshold intensity at anintermediate frequency, for example, 3000 Hz. Otherwise, the pure tonefrequency module concludes the procedure and returns the results to themain program module.

[0055] While the exemplary implementation of the pure tone frequencymodule described above started the pure tone testing at 1000 Hz, aperson having ordinary skill in the art will recognize that otherstarting points may be used without departing from the scope of theinvention. For example, the pure tone frequency module could start thetesting at 8000 Hz and work down to the lower frequencies to obtainessentially similar results. Also, the pure tone frequency module maytest frequencies above 8000 Hz, below 250 Hz, or at other interoctavefrequencies not mentioned above without departing from the scope of theinvention.

[0056] Turning now to FIG. 6, a flowchart 600 illustrates an exemplaryimplementation of the pure tone threshold module according to someembodiments of the invention. The pure tone threshold has theresponsibility of coordinating the various tasks required to determine athreshold intensity for each pure tone frequency tested. For each puretone frequency, the pure tone threshold module first obtains an unmaskedbone threshold at step 601 by calling the pure tone intensity module(described below). The pure tone threshold module thereafter uses theunmasked bone threshold to determine whether the left ear or the rightear is louder, provided this determination has not already been made ina previous iteration. If it turns out that the louder ear determinationhas already been made, then the pure tone threshold module can skip thisdetermination in the current iteration.

[0057] Thus, at step 602, the pure tone threshold module determineswhether the unmasked bone threshold just obtained is the first unmaskedbone threshold. If it is not, then that means the louder eardetermination has already been made in a previous iteration, and thepure tone threshold module may proceed directly to the better ear airthreshold test at step 607. If the unmasked bone threshold just obtainedis the first unmasked bone threshold, then at step 603, the pure tonethreshold module presents the frequency being tested to the patientusing an intensity level roughly equal to the unmasked bone thresholdplus a margin (e.g., 10 dB). The patient is then prompted at step 604 toindicate which ear can hear the frequency louder. Based on the patient'sresponse, either the left ear is marked as the better one (step 605) orthe right ear is marked as the better one (step 606). Note that thisstep is an optimization step and, if omitted, might make the test alittle longer, but would not alter the end results.

[0058] At step 607, for whichever ear was denoted as the better ear, thepure tone threshold module obtains an air threshold for that ear byagain calling the pure tone intensity module. The pure tone intensitymodule obtains an air threshold for the ear being tested and returns theresults to the pure tone threshold module. The pure tone thresholdmodule thereafter determines at step 608 whether the frequency beingtested is the first frequency, which is 1000 Hz in this embodiment. Ifit is not, the pure tone threshold module proceeds to step 611 to obtainthe air threshold for the other, poorer ear. On the other hand, if thefrequency being tested is the first frequency, then at step 609, thepure tone threshold module determines whether the unmasked bonethreshold is more than 20 dB worse than the air threshold just obtained.If it is not, the pure tone threshold module again proceeds to step 611.If the unmasked bone threshold is more than 20 dB worse than the airthreshold just obtained, the pure tone threshold module raises asuspicious bone threshold warning at step 610. In some embodiments, thepure tone threshold module also alerts the operator, as this is usuallyan indication that the bone conduction transducer is disconnected, noton the patient, or has otherwise failed. The pure tone threshold modulethereafter proceeds to step 611.

[0059] At step 611, the pure tone threshold module again calls the puretone intensity module to obtain the air threshold for the poorer ear. Atstep 612, the pure tone threshold module determines whether the air-bonegap for either ear is greater than or equal to a minimum significantair-bone gap, which might indicate that a masked bone threshold isneeded to establish the bone conduction of each ear. The minimumsignificant air-bone gap is about 10 dB according to some audiologists.Most people with normal hearing will have an air-bone gap that issmaller than this and, therefore, a masked bone threshold will not beneeded and the pure tone threshold module can proceed directly to step616.

[0060] If, however, the air-bone gap for either ear is greater than orequal to the minimum significant air-bone gap, then the pure tonethreshold module proceeds to obtain masked bone thresholds, beginningwith the poorer ear at step 613 (by calling the pure tone intensitymodule). The pure tone threshold module thereafter determines whetherthe masked bone and unmasked bone difference for that ear is less thanor equal to a maximum central masking effect. The central masking effectis a measure of the level of masking noise introduced at thecontralateral ear that can influence the audibility of tones at theipsilateral ear. The maximum central masking effect is considered bysome audiologist to be about 20 dB. If the poorer ear masked bonethreshold is worse than the unmasked bone threshold by more than thecentral masking affect, one can safely assume that the unmasked bonethreshold pertains to the better ear, and a separate threshold is notnecessary. If, however, the poorer ear masked bone versus unmasked bonedifference is less than or equal to the maximum central masking effect,then the pure tone threshold module proceeds to obtain the better earmasked bone threshold at step 615.

[0061] Note that steps 612 and 614 are optional time saving measures,since in most people with normal hearing, the pure tone threshold modulewill proceed directly to step 616 from these steps. At step 616, thepure tone threshold module reevaluates the masking levels used for eachthreshold obtained at steps 607, 611, 613, and 615 (if available) basedon the most recent threshold information for the frequency being tested.It is possible that an early masked threshold was obtained withinsufficient masking, since any conductive loss that may be present inthe masked (non-test) ear would not be known ahead of time. For thisreason, the masking level used for all thresholds at the frequency beingtested are reevaluated after each new threshold is obtained in orderensure use of the most recent threshold information in determiningappropriate masking levels. Reevaluation involves calculating theminimum masking level (described in more detail with respect to FIG. 9)using the most recent thresholds for the frequency being tested. If thenewly calculated minimum masking level and the level used to obtain thethreshold are different by more than a predetermined amount, then thethreshold that was obtained may not be correct.

[0062] At step 617, the pure tone threshold module determines whetherall masked thresholds have been correctly masked from the results ofstep 616. If they have, the pure tone threshold module concludes itsprocedure for the frequency being tested and returns the results to thepure tone frequency module. Otherwise, the pure tone threshold moduledetermines whether the better ear air masking (step 618) and poorer earair masking (step 619) were correct. If the air masking for either earwas incorrect, the pure tone threshold module repeats the air thresholdprocedure for the affected ear. The pure tone threshold modulethereafter determines whether the bone threshold exists and bone maskingwas correct for the poorer ear (step 620) and the better ear (step 621).If the determination is no for either ear, the pure tone thresholdmodule repeats the unmasked bone threshold procedure for the affectedear. The pure tone threshold module thereafter returns to step 617 todetermine once again whether all mask thresholds were correctly maskedfor the frequency being tested. This process is repeated until allnecessary thresholds are obtained with the proper masking levels.

[0063]FIG. 7 illustrates a flow chart 700 of an exemplary implementationof the pure tone intensity module according to some embodiments of theinvention. As mentioned above, the pure tone intensity module is calledby the pure tone threshold module in order to determine an individualthreshold intensity for the pure tone frequency being tested. The puretone intensity module presents the frequency being tested using a seriesof different intensity levels and checking each level to see if it is atthe patient's hearing threshold for that frequency. For each frequency,the pure tone intensity module begins by first determining the intensitylevel that should be used to start the testing. The pure tone intensitymodule then sets the masking level for that intensity level, and foreach subsequent intensity level as needed.

[0064] One key design feature of the pure tone intensity module is thedetection of a false response. If the intensity level testing reachesthe equipment lower limit and still no threshold has been found, thenthe patient may be guessing or trying to anticipate the tones. In someembodiments, the pure tone intensity module turns the intensity leveloff at this point and checks whether the patient heard a tone. If hedid, then the patient is given a false response warning, since he couldnot have heard a tone with the intensity turned off.

[0065] Another key design feature of the pure tone intensity module isthat it measures the level of ambient noise present during an ongoingtest. This allows the automated hearing test of the present invention tocompensate for the ambient noise. As a result, the automated hearingtest can be performed without a quiet room or a sound isolation chamber.The ambient noise may be measured at regular intervals, or at variouspredetermined points throughout the test. In some embodiments, theambient noise may be measured at the moment each intensity level isused. In this way, real time analysis of the ambient noise is performedfor each intensity level and can be compensated for as needed.

[0066] To determine the starting intensity level, the pure toneintensity module calls the pure tone initial intensity determinationmodule (described below) at step 701. It also calls the set pure tonemasking levels module at step 702 to determine the amount of masking forthat intensity level. At step 703, the pure tone intensity moduledetermines whether there is a problem with the masking level returned bythe set pure tone masking levels module. A masking problem may resultfrom equipment limitations (i.e., the masking level is beyond thelimitations of the audiometer or the transducer), or the problem may bedue to a masking dilemma. A masking dilemma occurs when the minimummasking level required at the non-test ear also masks the test ear dueto crossover, causing the threshold levels in the test ear to beshifted. When such masking problems occur, the pure tone intensitymodule simply concludes its procedure for the frequency being tested andreturns to the pure tone threshold module. In some embodiments, however,the pure tone intensity module may proceed anyway with unmaskedthresholds in the case of a masking dilemma.

[0067] If there is no masking problem, then the pure tone intensitymodule proceeds with the testing by starting the ambient noisemeasurement at step 704. The ambient noise may be measured using anymicrophones suitable for the task, such as those described in U.S.Provisional Patent Application entitled “System and Method forConducting Multiple Diagnostic Hearing Tests” mentioned above.Preferably, one microphone is placed near each ear, but it is alsopossible to place the microphones at other locations. At step 705, thepure tone intensity module determines whether the current masking levelis different from the previous iteration's masking level. Thisdetermination is important because a change in the masking level cansometimes clue the patient that a tone is about to be presented. Ifthere has been a change in the masking level, then the pure toneintensity module introduces a random delay (e.g., 0.5 to 3 seconds) atstep 706 before presenting the tone. On the other hand, if the maskinglevel did not change, but the patient responded to a prior stimulus atstep 707 (which could happen only on the second and subsequentiterations of this loop), the pure tone intensity module will stillintroduce a random delay before presenting the tone. If the patient didnot respond to a prior stimulus, however, then the pure tone intensitymodule proceeds with presentation of the tone pulse train at step 708.The presentation of the tone pulse train lasts about two seconds in someembodiments, but may be adjusted longer or shorter as needed. In someembodiments, a non-pulsed tone or frequency modulated tone (warble) maybe used in place of a pulsed tone.

[0068] At step 709, the pure tone intensity module concludes the ambientnoise measurement. This measurement will then be used to compensate forthe level of ambient noise if needed. The pure tone intensity modulethereafter determines at step 710 whether the patient responded prior tothe start of the tone presentation. Such a response may indicate thepatient is guessing or trying to anticipate the presentation of thetone. When this happens, the pure tone intensity module increments afalse response counter at step 711, and determines whether the currentmasking is the first time masking is used for the frequency under testat step 712. If it is, then the false response may have been due to thepatient not being ready for the sudden introduction of the maskingnoise. At this point, the pure tone intensity module internally raises afalse response warning at step 713 to the patient, and returns to theset pure tone masking levels step 702 so that the same tone presentationcan be repeated.

[0069] If the current masking is not the first time masking is used forthe frequency under test (step 712), then the pure tone intensity moduledetermines at step 714 whether the false response counter in step 711has exceeded a predetermined limit. The predetermined limit isarbitrarily set at three false responses in some embodiments, but may beadjusted higher or lower as needed. If the false response counter hasexceeded the predetermined limit, the pure tone intensity module raisesa false response warning at step 715, which can be used to alert theuser to respond only when they hear a tone. The pure tone intensitymodule thereafter resets the intensity level for the tone to the initialvalue at step 716, and returns to step 702 to begin the procedure again.

[0070] If the false response counter has not exceeded the predeterminedlimit, then the pure tone intensity module continues at step 717, whereit determines whether the patient responded before expiration of a postpresentation timeout period. The post presentation timeout period allowssome time for the patient to respond even after the tone pulse train hasstopped. This timeout period may be in the 0 to 2 second range; in thisembodiment, the time period is set to about 0.5 seconds If the patientdoes respond before the post presentation timeout period expires, thenthe pure tone intensity module determines at step 718 whether thatresponse occurred while the intensity level of the tone was off Theintensity level is turned off if the lower limit of the equipment hasbeen reached and still no threshold has been found. This means thepatient is probably trying to guess of anticipate the tones, as he couldnot have heard any tone while the intensity was turned off The pure toneintensity module thereafter proceeds to issue the false response warningat step 715.

[0071] On the other hand, if the intensity level was not off, then thepure tone intensity module checks at step 719 to see if a threshold hasbeen reached. The pure tone intensity module performs his task bycalling the threshold detection module (described below). Afterwards, adetermination is made at step 720 as to whether a threshold for thefrequency being tested was found. If a threshold was found, the puretone intensity module concludes its procedure for this frequency andreturns the results to the pure tone threshold module. If a thresholdwas not found, then at step 721, the pure tone intensity moduledetermines whether the current intensity level has reached theequipment's lower limit. If it has, then at step 722, the pure toneintensity module turns the intensity level off and returns to step 702where the procedure will be repeated with no tone. If the currentintensity level is not at the equipment's lower limit, then the puretone intensity module decreases the intensity level at step 723 by apredetermined increment and returns to step 702 to repeat the procedurewith the new intensity level.

[0072] Referring back to step 717, if the patient did not respond beforeexpiration of the post presentation timeout period, meaning there was nopatient response to the tone presentation, then the pure tone intensitymodule determines at step 724 whether the current intensity level hasreached the equipment's upper limit. If it has, then the pure toneintensity module records that the patient's threshold intensity for thefrequency being tested is above the equipment limit at step 725, andraises an internal warning at step 726. In some embodiments, the patientmay be asked to press an on-screen button at this point to indicate thatthey have not dozed off during the test. If the button is pressed in atimely manner, then the test can continue; if not, the operator may bepaged to wake the patient and help him get back to the task ofresponding to tones.

[0073] If the current intensity is not at the equipment's upper limit,then at step 727, the pure tone intensity module checks the level ofambient noise present. In some embodiments, the pure tone intensitymodule performs this check by determining whether the ambient noisethreshold shift is greater than or equal to the current intensity level.An ambient noise threshold shift occurs when the ambient noise level isgreater than the minimum level allowed by ANSI standards. The shift canbe determined, as known to persons having ordinary skill in the art, byperforming a frequency analysis of the ambient noise (measured at step704) and comparing the frequency components to ANSI minimumrequirements. If the shift is greater than or equal to the currentintensity level, then at step 728, the pure tone intensity moduleincrements an ambient noise repeat counter. The purpose of the counteris to ensure that any increase in the ambient noise is real and not justa temporary occurrence due to, for example, the patient coughing. Thus,the pure tone intensity module determines at step 729 whether theambient noise repeat counter is greater than a predetermined limit,meaning the increased ambient noise was detected several times. Thepredetermined limit is arbitrarily set at three in some embodiments, butmay be adjusted higher or lower as needed. In some embodiments thepredetermined limit can be set to zero so that presentations are neverrepeated. If the ambient noise repeat counter is less than thepredetermined limit, then at step 730, the pure time intensity moduleleaves the current intensity level as it is, and returns to step 702 torepeat the procedure with the intensity level unchanged. If the counteris greater than the predetermined limit, then at step 731, the pure toneintensity module increases the current intensity level by apredetermined increment, and returns to step 702 to repeat the procedurewith the new intensity level.

[0074]FIG. 8 illustrates an exemplary implementation of the pure toneinitial intensity determination module, called by the pure toneintensity module to determine the initial testing intensity. In someembodiments, it is possible to simply start at one end of the availableintensity spectrum and gradually progress to the other end. Such aprocess is inefficient, however, as some intensities may beunnecessarily tested. For example, if the patient's threshold intensityfor the ear and frequency being tested is actually 20 dB, then it wouldbe inefficient to start testing at 0 dB rather than, say, 10 dB. Thepure tone initial intensity determination module therefore tries tochoose a starting intensity that would eliminate at least some of theunnecessary intensities. It does this by identifying existing thresholdintensities, if any, for the same ear, but taken from a differentiteration of the module or a different session of hearing test. The puretone initial intensity determination module then chooses a startingintensity level based on the existing threshold. If there are noexisting thresholds, the pure tone initial intensity determinationmodule uses an ascending intensity sweep algorithm to determine astarting intensity.

[0075] As can be seen from the exemplary flowchart 800, the first stepis to determine whether a threshold intensity already exists for aparticular transducer (e.g., bone or air conduction), frequency and earbeing tested at step 801. The reason for this determination is someexisting thresholds might need to be retested because of, for example,new information obtained about the opposite ear. The existing thresholdmay be from a previous iteration of the module or a previous session ofthe hearing test provided the data is not too old (e.g., less than sixmonths). If one does exist, then the next step is to determine whetherthat existing threshold intensity is at the equipment's upper intensitylimit at step 802. If a threshold intensity is not at either the low orhigh limit of the equipment, then the pure tone initial intensitydetermination module sets the initial tests intensity equal to thethreshold intensity plus a predetermined margin at step 803. Thepredetermined margin is 5 dB in some embodiments, but may be adjustedhigher or lower as needed. The pure tone initial intensity determinationmodule thereafter concludes its procedure and returns the results to thepure tone intensity module.

[0076] If a threshold intensity does not already exists at step 801, orif the existing threshold intensity is at the equipment's upper or lowerlimit at step 802, the pure tone initial intensity determination moduledetermines whether a bone threshold intensity exists for the frequencyand the ear being tested at step 804. If the determination is no, thepure tone initial intensity determination module determines at step 805whether a threshold intensity already exists for the ear being tested ata lower frequency. If the determination is again no, the pure toneintensity determination module determines at step 806 whether a bonethreshold intensity already exists for the ear being tested at a lowerfrequency. If the determination is yet again no, then the pure toneinitial intensity determination module proceeds to step 807, where ituses the sweep starting intensity as the initial sweep intensity for theascending intensity sweep algorithm. In some embodiments, the sweepstarting intensity is 20 dB, but may depend on the equipment being used.At step 808, the pure tone initial intensity determination modulepresents the pure tone frequency being tested at an intensity levelequal to the initial sweep intensity, but with a shorter duration than anormal tone presentation. A determination is made at step 809 as towhether the patient responded to the tone presented. If he did notrespond, then the intensity of the tone is increased by a predeterminedincrement at step 810, and the tone is presented again. If the patientdid respond, then at step 811, the initial intensity is set equal to theintensity of the current tone rounded down to the nearest 5 dB. Using ashorter sweep pulse with rapid increases in intensity in the absence ofpatient responses allows a very rough approximation of threshold to bequickly determined. This approximation forms the starting point for morerigorous threshold determination. The pure tone initial intensitydetermination module thereafter concludes its procedure and returns theresults to the pure tone intensity module.

[0077] If the determination made at any of steps 804, 805, and 806 isyes, then the pure tone initial intensity determination module proceedsto step 812, where it determines whether the existing threshold is atthe equipment's lower intensity limit. If it is, then the pure toneinitial intensity determination module sets the initial tests intensityto 0 dB at step 813 and returns the results to the pure tone intensitymodule. If the existing threshold is not at the equipment's lowerintensity limit, then at step 814, a determination is made as to whetherthe existing threshold is at the equipment's upper intensity limit. Ifit is, the pure tone initial intensity module continues to step 807 andproceeds as described above. If it is not, the pure tone initialintensity determination module sets the sweep starting intensity equalto the existing threshold minus a predetermined margin (e.g., 5 dB). Thepure tone initial intensity determination module continues to step 808and proceeds as described above.

[0078]FIG. 9 illustrates a flowchart 900 for an exemplary implementationof the set pure tone masking levels module according to some embodimentsof the invention. Masking prevents the non-test ear from hearing thetone presented in the test ear due to crossover. Crossover is aphenomenon in which sound presented in one ear propagates through theskull and stimulates the opposite ear. This phenomenon is frequencydependent, that is, certain frequencies propagate through the skullbetter than others. The phenomenon is also transducer dependent; forexample, the crossover is different for insert earphones than forheadphones at a given frequency. Masking introduces a narrow band signalin the non-test ear centered around the frequency being tested in orderto “mask” the sound that has crossed over. It is important, however, touse the correct intensity level for the masking noise. Too little noisemay be insufficient to mask the sound, while too much noise may have areverse crossover effect (i.e., the masking noise crosses over and isaudible in the test ear). Sometimes it is possible to arrive at thecorrect masking level by monitoring the shift in the threshold of thetest ear for each masking level. A linear shift, for example, mayindicate the threshold of the test ear is tracking the masking noise inthe non-test ear, which may mean there is too much masking. Thisprocess, however, is not very efficient. Therefore, the purpose of theset pure tone masking levels module is to quickly determineapproximately the right levels of masking for the frequency beingtested.

[0079] The set pure tone masking levels module determines theappropriate amount of masking by first determining a minimum requiredamount of masking. This minimum masking level should be sufficient toovercome any loss in the non-test ear in addition to any crossover. Itshould be noted that, in general, a masking level that is somewhathigher than the minimum required is acceptable, but an insufficientamount of masking can lead to erroneous results. If it turns out thatthe minimum amount of masking required for the patient is very low(i.e., below a predefined turn-on criteria), then no masking is used, asit would have neutral or no benefit.

[0080] Otherwise, the set pure tone masking levels module sets themasking at a level that is a little higher than the minimum required.The reason for doing so is that a higher masking level makes it easierfor the patient to distinguish the masking from a faint tone. Also, eachchange in the masking level may alert the patient to the tonepresentation. Therefore, the set pure tone masking levels modulesimplements a hysteresis by setting the masking at a level that is alittle higher than the minimum required. This allows multiple ascendingtone presentations to be made before having to make adjustments to themasking level.

[0081] As can be seen from the flowchart 900, the first step is todetermine whether unmasked bone is currently being tested at step 901(see step 601 in FIG. 6). If it is, then there is no need to set amasking level, and the set pure tone masking levels module concludes itsprocedure and returns to the previous module. If unmasked bone is notbeing tested, then at step 902, the set pure tone masking levels modulecalculates the amount of crossover expected for the frequency beingtested. In some embodiments, the crossover calculations are based onwell known inter-aural attenuation tables, an example of which is shownin Table 1 below. TABLE 1 INTER-AURAL ATTENUATION Attenuation Frequency(Hz) (dB) 250 500 1000 2000 3000 4000 6000 8000 Min. 44 54 57 55 56 6156 51 Max. 58 65 66 72 72 85 76 69 Mean 51 59 61 61 68 70 65 57

[0082] Using the mean values from Table 1 above, the amount ofattenuation expected for a 500 Hz tone is about 59 dB. Thus, at thisfrequency, a tone that has a presentation level of less than 59 dB wouldnot produce any crossover and would not need to be masked. On the otherhand, a tone that has a presentation level of, say, 65 dB, would produceabout 6 dB of crossover that would need to be masked.

[0083] Once the crossover values have been calculated for the frequencybeing tested, the set pure tone masking levels module calculates at step903 the minimum required masking level and the maximum allowable maskinglevel for the frequency being tested. The minimum masking level, ingeneral, is the lowest level of masking that can still mask anycrossover in the non-test ear. In some embodiments, the minimum maskinglevel is defined as a sum of the crossover plus the non-test earair-bone gap. The crossover can be determined from the inter-auralattenuation tables as described above. The non-test ear air-bone gap, atleast initially, is assumed to be 0 dB. In some embodiments, a margin of5 dB may be added to the minimum masking level in order to ensure thereis sufficient masking, although the masking margin may be adjustedhigher or lower as needed. The maximum masking level is the level beyondwhich masking in the non-test ear will be heard in the test ear at alevel sufficient to mask the test signal being presented. In someembodiments, the maximum masking level may be defined as that levelwhich, when one subtracts the masking inter-aural attenuation, resultsin the effective presentation level. The effective presentation level isthe intensity level of the tone as it is received at the inner ear. Forair testing, the effective presentation level is the air conductionintensity level minus the air-bone gap. For bone testing, the effectivepresentation level is about equal to the bone conduction level.

[0084] At step 904, set pure tone masking levels module determineswhether the minimum masking meets the masking turn-on criteria. Theturn-on criteria is 0 dB in some embodiments, but may be adjusted higheras needed. If the turn-on criteria is met, then at step 905, the set airtone masking levels module makes sure that the minimum masking is atleast set to the minimum masking presentation level. The minimum maskingpresentation level is 20 dB in some embodiments, but may be adjustedhigher or lower as needed. If the turn-on criteria is not met, the setpure tone masking levels module determines at step 906 whether theminimum masking level is louder than the current masking level. If it isnot, then the set pure tone masking levels module determines at step 907whether the minimum masking level is much softer (e.g., about 25 dB)than the current masking level. If it is again not, then the set puretone masking levels module makes no change to the current masking levelat step 908. Note that steps 907 and 908 are optional and are intendedto act as the hysteresis function to prevent small or insignificantchanges from being made to the masking level. In general, the fewerchanges that are made to the masking level, the better, since eachchange is distracting and can potentially alert the patient that a toneis about to be presented.

[0085] If the minimum masking level determined in step 903 is louderthan the current masking level (step 906), or if the minimum maskinglevel is much softer than the current masking level (step 907), then atstep 909, the set pure tone masking level module sets the new maskinglevel equal to the minimum masking level. At step 910, the set for tonemasking levels module determines whether the new masking level is soloud as to mask the test ear. If it is, then the set pure tone maskinglevels module sets the new masking level just below the maximum maskinglevel at step 911, and determines whether this new masking levelprovides a sufficient amount of masking at step 912, that is, whetherthe new masking level is greater than or equal to the minimum maskinglevel calculated at step 903. If the new masking level is not loudenough, then the set pure tone masking levels module raises anindication that there is a masking dilemma at step 913.

[0086] On the other hand, if the new masking level is sufficiently loud,then at step 914, the set pure tone masking levels module determineswhether the new masking level will be louder than the equipment'sloudest level. If it is, then the set pure tone masking levels modulesets the new masking level just below the equipment's limit at step 915.The set pure tone masking levels module thereafter determines at step916 whether this new masking level is sufficient to mask. If it is not,then at step 917, the set pure tone masking levels module raises anindication that the resulting threshold will be undermasked. If it is,then the set pure tone masking levels module determines whether the newmasking level is audible in the non-test (masked) ear. If the newmasking level is not audible in the non-test ear, then in someembodiments, masking is simply turned off at this point.

[0087] In some embodiments, however, the operator is given the option ofrequiring masking to be on for all bone conduction testing. If thatoption is exercised (e.g., via an internal flag), then the set pure tonemasking levels module determines at step 919 whether bone conduction iscurrently being tested, and whether masked bone conduction is required(i.e., the internal flag is set). If this determination is yes, then atstep 920, the set pure tone masking levels module sets the new maskinglevel equal to the minimum presentation level that is still audible, asdetermined by the greater of the minimum configurable masking intensity,the minimum mask turn-on level (e.g., 0 dB), and the air threshold forthe non-test ear (where available). This allows the automated hearingtest to obtain a masked bone threshold for the ear being tested eventhough the minimum calculated masking level would not have been heard bythe patient.

[0088] If bone conduction is not currently being tested, or if maskingis not required for all bone threshold tests, then masking may be turnedoff at step 921. Thereafter, the set pure tone masking levels moduledetermines whether masking is being attempted for the first time at step922. If it is, then the set pure tone masking levels module warns thepatient that masking is about to begin at step 923. If it is not, as inthe case when masking is turned off, the set pure tone masking levelsmodule concludes its procedure and returns the results to the pure toneintensity module. In some embodiments, after step 921, the set pure tonemasking levels module may proceed directly to the conclusion of theprocedures.

[0089]FIG. 10 illustrates a flowchart 1000 for an exemplaryimplementation of the threshold detection module according to someembodiments of the present invention. This module is the one called bythe pure tone intensity module (FIG. 7) to determine whether a thresholdintensity has been reached. The threshold detection module makes thisdetermination by comparing the current intensity to a number ofpredetermined milestones or indicators. Depending on the comparisons,the threshold detection module records the threshold, if any, as a Type1, 2, or 3 category threshold. These threshold types are arbitrarilyassigned to indicate there are different ways that a threshold may bedetected. In general, certain approaches to threshold determination maybe optimal for speech thresholds, while other approaches are optimal forpure tone thresholds. The threshold detection module accommodates thedifferent approaches by implementing more than one way to establish athreshold. Although only three threshold types are discussed, otherthreshold detection techniques may certainly be added to the thresholddetection module as needed. Another key design feature of the thresholddetection module is that it checks to make sure that the thresholdreached was not significantly affected by any ambient noise that mayhave been present.

[0090] The first step that is performed by the threshold detectionmodule is to determine whether the patient failed to respond at theequipment's upper intensity limit at step 1001. If he did, then thethreshold detection module notes that the patient's threshold intensityfor the frequency being tested is beyond the limit of the equipment atstep 1002, and thereafter concludes its procedure. If the patient didrespond at or below the equipment's upper intensity limit, then at step1003, the threshold detection module proceeds to calculate severalmilestones or indicators, including: (T) total number of responses atintensities within 15 dB of the current intensity, (R) number ofresponses at the current intensity, (NR) number of non-responses at thecurrent intensity, (NL) number of responses that are unaffected byambient noise at the next lower intensity, (V) the number of reversalsin the direction of progression of the intensity presentations, and (M)the average of the intensity values where reversals have occurred,excluding the first two values in some embodiments. It should beemphasized that these particular milestones or indicators are exemplaryonly, and that other milestones or indicators may also be used withoutdeparting from the scope of the invention.

[0091] After the milestones or indicators have been calculated, thethreshold detection module in one embodiment proceeds to step 1004,where it determines whether the current threshold detection is forspeech reception threshold (i.e., the module was called by the speechreception threshold module). If it is not, the threshold detectionmodule determines whether the current threshold detection is the firstthreshold detection at step 1005. If it is the first thresholddetection, then one embodiment of the threshold detection moduleincreases the minimum response count to allow for training purposes atstep 1006. For example, usually the minimum response count may be setequal to two, but may be equal to three or more for the first thresholddetection to allow the patient to become familiar with the procedure.

[0092] If the current threshold detection is not the first thresholddetection, the threshold detection module proceeds directly to step 1007to determine whether the current intensity level is greater than theprevious intensity level, i.e., greater than the intensity level usedthe last time the threshold detection module was called. If it isgreater, then at step 1008, the threshold detection module determineswhether the number of responses at the current intensity level exceedsthe minimum response count. If it does exceed the minimum responsecount, then at step 1009, the threshold detection module determineswhether the number of responses at the current intensity level ( ) isgreater than the number of non-responses at this intensity level (NR) If(R) is not greater than (NR), then at step 1010, the threshold detectionmodule determines whether the ratio of the number of responses at thecurrent intensity level (R) over the total number of responses atintensities within 15 dB of this intensity (T) is greater than theminimum response ratio. In some embodiments, the minimum response ratiois set to one-half, but may be adjusted higher or lower as needed. Theratio (R)/(T) can indicate whether the responses are being clustered orgrouped together around a certain intensity level, which may indicatethe patient has a threshold at that intensity level.

[0093] If (R)/(T) is greater than the minimum response ratio in step1010, then the threshold detection module indicates that a threshold hasbeen reached, and assigns it a Type 2 for internal usage. The thresholddetection module thereafter determines at step 1012 whether the numberof non-responses that are unaffected by ambient noise at the next lowerintensity level is greater than or equal to a minimum value. The minimumvalue may be one in some embodiments, but may be adjusted higher asneeded. If (NL) is greater than or equal to the minimum value, thenambient noise was not a significant factor in the threshold detection,and the threshold detection module concludes its procedure and returnsto the pure tone intensity module. Otherwise, if (NL) is less than theminimum value, then at step 1013, the threshold detection module marksthe resulting threshold as possibly shifted by ambient noise.

[0094] If, on the other hand, (R) is greater than (NR) at step 1009, thethreshold detection module indicates that a threshold has been reachedat step 1014, and assigns it a Type 1 for internal use. The thresholddetection module then proceeds to step 1012 for the affected by ambientnoise check.

[0095] Furthermore, if the current intensity level is not greater thanthe previous intensity level (step 1007), or (R) is not greater than theminimum response counter (1008), or (R)/(T) is not greater than theminimum response ratio (step 1010), then there is no threshold detected,and the threshold detection module simply concludes its procedure.

[0096] If it turns out that the current threshold detection is for aspeech threshold (step 1004), then at step 1015, the threshold detectionmodule determines whether the patient responded correctly at theequipment's lower intensity limit. If he did, then at step 1016, thethreshold detection module notes that the patient's threshold intensityis below the equipment's lower intensity limit. If the patient did notrespond correctly at the lower intensity limit, then at step 1017, thethreshold detection module determines whether the number of reversals(V) is greater than or equal to a reversal limit. In some embodiments,the reversal limit is four, but may be adjusted higher or lower asneeded. If (V) is not greater than or equal to the reversal limit, thenthe current intensity is not a threshold, and the threshold detectionmodule concludes its procedure. Otherwise, the threshold detectionmodule notes that a threshold has been reached at an intensity levelequal to the average of the intensity values where reversals haveoccurred (M) at step 1018, and assigns it a Type 3 for internal use. Thethreshold detection module then proceeds to step 1012 for the affectedby ambient noise check.

[0097]FIG. 11 illustrates a flowchart 1100 for an exemplaryimplementation of the speech reception threshold module according tosome embodiments of the invention. The speech reception threshold moduleis called by the main program module to perform the speech receptionthreshold test. In some embodiments, the speech reception thresholdmodule calculates a best performance intensity level and an expectedperformance intensity level according to a performance intensity (PI)curve. The PI curve is a prediction of the patient's performance atvarious intensity levels based on an Articulation Index (AI). The AI isa mathematical formula that is used to predict the word recognitionability of normal listeners given any combination of test material,frequency filter, level, and noise. For more information about AI andthe PI curve, see “The articulation index in clinical diagnosis andhearing aid fitting,” by Chris Halpin, PhD, Aaron Thornton, PhD, andZezhang Hous, PhD, Current Opinion in Otolaryngology & Head and NeckSurgery, 4:325-334, 1996.

[0098] The speech reception threshold module then uses the bestperformance intensity level and the expected performance intensity levelto control the intensity levels of the speech reception threshold test.Such an arrangement helps avoid having to start the speech receptionthreshold test at an intensity level that is too low or too high. Ifthere is no existing data on the patient from which to calculate theseintensity points, then the speech reception module starts with a fairlyloud volume, for example, 60 dB, then quickly steps the intensity downuntil the patient can no longer hear the presentations. After that, theintensity levels are adjusted in smaller increments. If data exists, thespeech reception threshold module sets the starting intensity leveldirectly to the expected performance intensity level and increases ordecreases it in small increments to reach a threshold intensity.

[0099] The speech reception threshold module then presents a set ofrandomly chosen pictures to the patient along with the words for thepictures. In some embodiments, the same set of randomly chosen picturesis used for the entire test, although it is possible to use more thanone set. Preferably, the words that are used are compound words with twodistinct syllables. For languages where no such words are used,appropriate substitutes may be made. The words are randomly presentedone at a time to the patient with no emphasis on any syllable. Thespeech reception threshold module then waits for the patient to selectthe picture matching the word presented. For the first intensity level,a single response, whether correct or incorrect, initiates the thresholddetection procedure. For each subsequent intensity level, two or moreresponses are needed, whether correct or incorrect, before thresholddetection is initiated. In some embodiments, two consecutive wrongchoices result in an incorrect answer, and two consecutive right choicesresult in a correct answer. Where there is one wrong choice followed byone right choice, the next choice determines whether the answer iscorrect or incorrect.

[0100] Referring now to FIG. 11, at the first step 1101, the speechreception threshold module determines whether all of the pure tonethresholds are at the upper limit of the equipment. If they are, thenthat means the ear being tested is not capable of hearing any tones(i.e., the ear is a dead ear). At this point, the speech receptionthreshold module simply notes that the ear could not be tested at step1102. The speech reception threshold module thereafter concludes itsprocedure and returns to the calling module.

[0101] If the ear is not a dead ear, then at step 1103, the speechreception threshold module determines whether there is a masking dilemmaat any of the pure tone average (PTA) frequencies of 500 Hz, 1000 Hz and2000 Hz. If there is a masking dilemma, then the speech receptionthreshold module again notes that the ear could not be tested at step1102. If, however, there is no masking dilemma, then at step 1104, thespeech reception threshold module calculates the best and expectedperformance intensity levels. The best performance intensity level(PBTest) is the highest point on the PI curve and is the intensity levelwhere the patient should get the most correct responses to wordpresentations. The 50 percent performance intensity level (PredictedSRT)is the middle point of the PI curve and is the point where the patientshould correctly respond to about half of all presentations.

[0102] After PBTest and PredictedSRT have been calculated, the speechreception threshold module randomly chooses a set of word-picture pairsat step 1105. Nine word-picture pairs are used in the exemplaryembodiment, but fewer or more word picture pairs may be used.Preferably, there are enough pictures to limit the possibility ofcorrect guessing while at the same time make identifying the correctpicture a simple task. In some embodiments, a method of indicating noneof the above or word not understood may be provided, either in additionto or in place of one of the pictures. In the English language, thewords chosen are known as “spondees” and usually have two distinctivesounding syllables uttered with equal accent on each syllable. In otherlanguages, the words may have more than two syllables. At step 1106, thespeech reception threshold module presents the set of pictures on thedisplay screen. At step 1107, the speech reception threshold module setsthe starting intensity equal to PredictedSRT. In some embodiments, thespeech reception threshold module also adds a small training margin, butdoes not set the starting intensity to be louder than PBTest.

[0103] At step 1108, the speech reception threshold module sets thetrial size equal to one for the initial intensity decrease. The speechreception threshold module thereafter initializes a count of correctresponses and count of incorrect responses to zero at step 1109. Next,the speech reception threshold module checks to see if the word queue isempty at step 1110. If it is, the speech reception threshold modulefills the word queue at step 1111 with non-repeating words correspondingto the pictures that are displayed. In some embodiments, the word queuecontains four words randomly selected from the set of available words,but larger or smaller word queue sizes can be used. The speech receptionthreshold module thereafter chooses and removes one of the words fromthe queue at step 1112, and sets the speech masking level module at step1113. The speech reception threshold module sets the speech maskinglevel by calling the set speech masking level module (described below)and passing the appropriate information thereto. Once masking isinitiated, the speech reception threshold module presents the word atthe current intensity at step 1114, and waits for a predefined period oftime for the patient to respond at step 1115. The waiting period in someembodiments is 3 seconds, but may be longer or shorter.

[0104] At step 1116, a determination is made as to whether the patientresponded. If he did not respond, then at step 1117, the speechreception threshold module raises a no picture was chosen warning to thepatient, and returns to step 1115 to await the patient's response. Thiswarning may take the form of an on-screen message, a verbal indicationpresented via the insert earphones, or both. In some embodiments, theoperator is paged if the patient repeatedly fails to respond in order towake the patient if needed or otherwise to help him complete the pictureselection task. If the patient did respond, then at step 1118, thespeech reception threshold module determines whether the patient pickedthe correct picture. If the patient picked the wrong picture, the speechreception threshold module increments the wrong-count counter at step1119. Otherwise, the speech reception threshold module increments thecorrect-count counter at step 1120. Thereafter a determination is madeat step 1121 to determine if the wrong-count counter is greater than aminimum count. In some embodiments, the minimum count is the trial sizedivided by two. Note that for the starting intensity, since the trialsize is initially one, any response will push either the wrong-countcounter or the correct-count counter over the minimum count. If thewrong-count counter is not greater than the minimum count, then thespeech reception threshold module determines at step 1122 whether thecorrect-count counter is greater than a minimum count. If thecorrect-count counter is also not greater than the minimum count, thenno score is given at step 1123, and the speech reception thresholdmodule returns to step 1110 to present the next word from the queue.

[0105] On the other hand, if the correct-count counter is greater thanthe minimum count, then at step 1124 the speech reception thresholdmodule scores the response as speech correctly heard. Similarly, if thewrong-count counter is greater than the minimum count, then at step1125, the speech reception threshold module scores the response asspeech not correctly heard. At step 1126, the speech reception thresholdmodule resets the trial size equal to the speech threshold trial size.In some embodiments, the speech threshold trial size is three, but maybe adjusted higher as needed. At step 1127, the speech receptionthreshold module sets the descending intensity interval equal to theascending intensity interval. In some embodiments, the initialdescending intensity interval is set to 10 dB and the initial ascendinginterval is set to 5 dB.

[0106] Thereafter, the speech reception threshold module determineswhether the current intensity is a threshold intensity at step 1128, bycalling the threshold detection module (see FIG. 10). A determination isthen made at step 1129 as to whether a threshold intensity was detectedby the threshold detection module. If a threshold was indeed detected,then the speech reception threshold module concludes its procedure andreturns the results to the main program module. If a threshold was notdetected, then at step 1130, the speech reception threshold moduledetermines whether the response was scored as speech correctly heard. Ifthe response was scored a speech not correctly heard, then at step 1131,the speech reception threshold module increases the intensity by anamount equal to the ascending interval. Otherwise, if the response wasscored as speech correctly heard, then the speech reception thresholdmodule decreases the intensity by an amount equal to the descendinginterval. Thereafter, the speech reception module returns to step 1109to present the next word.

[0107] Note that in the foregoing embodiments the trial size is set toone at the start and subsequently increased. The beginning trial size isset at one so that, initially, every picture choice is scored as eitherheard or not heard. This lets the output level quickly descend from itsstarting level to a level approximately where the threshold will be.Once the patient misses a word, the trial size is increased in order toensure that a legitimate response is received. For example, by requiringtwo out of three picture choices to ascertain whether the patient hearsat the current level, the chance of the patient making a lucky guess isreduced (e.g., from {fraction (1/9)} to {fraction (2/81)}).

[0108]FIG. 12 illustrates a flowchart 1200 for an exemplaryimplementation of the set speech masking levels module according to someembodiments of the invention. The set speech masking levels module iscalled by the speech reception threshold module to determine anappropriate masking level for the non-test ear. In this regard, the setspeech masking levels module has some similarities to the set pure tonemasking levels module (see FIG. 9) described previously. For example,the set speech masking levels module uses a minimum masking level and amaximum masking level to control selection of the masking noiseintensity. Such an arrangement helps avoid having to start selection ofthe masking noise intensity at a level that is too low or too high. Theset speech masking levels module also implements a hysteresis in orderto avoid making small, incremental changes to the masking level.

[0109] As can be seen in step 1201, the set speech masking levels modulecalculates a minimum masking level and a maximum masking level from theArticulation Index. In some embodiments, the minimum masking level maybe defined as the level of masking noise that makes any speech crossingover to the non-test ear unintelligible. If desired, a masking marginmay be added (e.g., 5 dB) to ensure that the minimum masking level willnot be too low. The maximum masking level, on the other hand, may bedefined as the level of masking noise beyond which, if one subtractedthe masking interaural attenuation, will have the undesirable effect ofmasking the speech presented in the test ear.

[0110] Once these minimum and maximum masking noise intensity levelshave been calculated, then at step 1202, the set speech masking levelsmodule determines whether the minimum masking level is louder than thecurrent masking level (e.g., from a previous iteration of the set speechmasking levels module). If it is, then the set speech masking levelsmodule sets the new masking level equal to the minimum masking level atstep 1203. Otherwise, the set speech masking levels module determines atstep 1204 whether the minimum masking level is much softer (e.g., morethan 25 dB softer) then the current masking level. If the minimummasking level is much softer, then the new masking level is set to theminimum masking level (step 1203). On the other hand, if the minimummasking level is not much softer than the current masking level, then nochange is made to the current masking level at step 1205. Note thatsteps 1204 and 1205 are optional steps that serve as a hysteresis toprevent small or minor changes in the masking level from being made.

[0111] At step 1206, the set speech masking levels module determineswhether this new masking level is so loud as to cross over and mask thetest ear. If it is, then at step 1207, the set speech masking levelsmodule sets the new masking level just below the maximum masking levelcalculated above. Otherwise, at step 1208, the set speech masking levelsmodule determines whether the new masking level will be louder than theequipment's upper intensity limit. If so, then at step 1209, the setspeech masking levels module sets the new masking level to just belowthe upper limit of the equipment. If not, at step 1210, the set speechmasking levels module determines whether the new masking level providesa sufficient level of masking noise, that is, a level equal to orgreater then the previously calculated minimum masking level. If the newmasking level provides an insufficient level of masking, then the setspeech masking levels module reports the new masking level as resultingin a masking dilemma, and concludes its procedure. Otherwise, the setspeech masking levels module determines at step 1212 whether the newmasking level meets the masking turn-on criteria (typically, 0 dB) If itdoes not, then masking is turned off at step 1213, and the set speechmasking levels module thereafter concludes its procedure. Otherwise, theset speech masking levels module simply concludes its procedure (i.e.,without turning masking off).

[0112]FIG. 13 illustrates a flowchart 1300 for an exemplaryimplementation of the speech discrimination module according to someembodiments of the invention. The speech discrimination module is calledby the main program module to perform speech discrimination testing.Unlike the pure tone threshold module or the speech reception thresholdmodule, the speech discrimination module does not test the patient'sthreshold intensity. Rather, the speech discrimination module uses anintensity level that is most likely to result in the patient being ableto hear the speech. The speech discrimination module thereafterdetermines how well the patient is able to discern between similarsounding words.

[0113] The words are preferably single syllable words that sound alike.For languages where such words are not available, appropriateadjustments may be made. A group of pictures is presented for each word.In some embodiments, the same pictures are used for each word. It ispossible that some pictures will overlap from word to word, but thereshould no repeats of entire picture sets. The speech discriminationmodule randomly chooses the groups of pictures from a large pool of suchpicture groups, then presents the words at a constant level, one at atime, with each group of pictures. The speech discrimination modulethereafter waits for the patient to respond.

[0114] The speech discrimination module concludes it procedure wheneither a sufficient percentage of correct responses has been received(e.g., 85 percent), or a large enough sample has been obtained to givean accurate assessment. In some embodiments, the percentage of correctresponses is evaluated on a word by word basis, with a predeterminedminimum of, for example, 10 correct words. Thus, if the patient respondscorrectly for the first 10 words, there is no need to continue testing,and the speech discrimination module may conclude its procedure byissuing a score of 100 percent speech discrimination accuracy.Similarly, if after 50 words, the patient has only chosen 20 of thecorrect pictures, then again there is probably no need to continuetesting. In the latter case, the speech discrimination module issues ascore reflecting the appropriate speech discrimination accuracypercentage (e.g., 60 percent discrimination loss). If, on the otherhand, after 15 words the patient has only given 12 correct answers, thenthe speech discrimination module continues with testing until thetermination conditions have been met.

[0115] In the first step 1301, the speech discrimination moduledetermines whether all of the pure tone thresholds are at the upperlimit of the equipment. If they are, then that means the ear beingtested is not capable of hearing any tones, i.e., the ear is a dead ear.At this point, the speech discrimination module simply notes that theear could not be tested at step 1302. The speech discrimination modulethereafter concludes its procedure and returns to the calling module.

[0116] If the ear is not a dead ear, then at step 1303, the speechreception threshold module determines whether there is a masking dilemmaat any of the PTA frequencies. If there is a masking dilemma, then thespeech discrimination module again notes that the ear could not betested at step 1302. If there is no masking dilemma, then at step 1304,the speech discrimination module calculates PBTest for the patient.Recall that PBTest is the close to the highest point on the PI curve andis the intensity level where the patient should have the best chance tocorrectly respond to presentations. If there is no data from which tocalculate PBTest, then the speech discrimination module sets theintensity level to a fairly loud volume, for example, 60 dB.Alternatively, the speech discrimination module may use an average ofthe pure tone intensities (if available) plus some predetermined margin(e.g., 40 dB). In other embodiments, it is also possible to let thepatient adjust the intensity to a volume that he's comfortable with.

[0117] After PBTest has been calculated, the speech discriminationmodule randomizes and queues several groups of word-picture pairs atstep 1305. In some embodiments, there are four word-picture pairs pergroup, and a total of about 100 groups, although these numbers may beadjusted higher or lower as needed. The four word-picture pairs within agroup are selected such that the words sound similar to each other. Atstep 1306, the speech discrimination module sets the intensity level ofthe presentation equal to PBTest. At step 1307, the speechdiscrimination module sets the masking level so that each ear can betested. (why do we need masking, are we testing each ear separately?),for example, by calling the set speech masking levels module (FIG. 12).At step 1308, the speech discrimination module clears three separatecounters: a correct-count counter, a wrong-count counter, and atotal-count counter.

[0118] At step 1309, the speech discrimination module displays the fourpictures in the group of word-picture pairs that is up next in thequeue. The speech discrimination module thereafter presents one of thewords from the group of four word-picture pairs, and waits for thepatient to respond at step 1311. At step 1312, the speech discriminationmodule determines whether the patient has responded. If there is noresponse, the speech discrimination module issues a no picture chosenwarning to the patient at step 1313 and returns to step 1311 to awaitthe patient's response. Otherwise, the speech discrimination moduleproceeds to step 1314 where it increments the total-count counter. Adetermination is made at step 1315 as to whether the patient chose thecorrect picture. If the patient chose the correct picture, then at step1316, the correct-count counter is incremented. If the patient did notchoose the correct picture, then at step 1317, the wrong-count counteris incremented.

[0119] Thereafter, at step 1318, the speech discrimination moduledetermines whether the total-count is greater than a predeterminedminimum, for example, 12 words. If the total-count is less than or equalto the predetermined minimum, then the speech discrimination modulereturns to step 1309, where it presents the next group of four picturesin the queue. If the total-count is greater than the predeterminedminimum, then at step 1319, the speech discrimination module determineswhether the total-count is greater than a predetermined maximum, forexample, 100 words. If it is, then the speech discrimination moduleproceeds to step 1320, where it corrects the final score to compensatefor any guessing. In some embodiments, the speech discrimination modulecompensates for guessing by determining the following: p the number ofpictures displayed for each word (nominally 4); n the number of wordspresented; s the number of words actually correctly heard by thepatient; g the number of words not correctly heard by the patient butguessed correctly; and c the number of correct picture choices made bythe patient whether heard or not heard, e.g. the correct-count counterdescribed above. By these definitions, c=s+g. Furthermore, the expectedvalue of g is (n−s)/p, as it represents the score one would get byguessing each of the (n−s) unheard words from p pictures. Solving for syields: s=(pc−n)/(p−1).

[0120] On the other hand, if the total-count is less than or equal tothe predetermined maximum, then the speech discrimination moduleproceeds to step 1321, where it calculates an error range andtermination conditions from the correct-count and wrong-count. At step1322, the speech discrimination module determines whether thetermination conditions have been met. If they have not, then the speechdiscrimination module returns to step 1309, where it presents the nextset of four pictures in the queue. If the termination conditions havebeen met, then the speech discrimination module proceeds to step 1320,where it corrects the final score to reflect any guessing and concludesthe procedure.

[0121]FIG. 14 illustrates a flowchart 1400 for an exemplaryimplementation of the patient management module according to someembodiments of the invention. The patient management module is called byother modules to keep the patient on track and the testing runningsmoothly. Thus, if the patient is not responding, or is responding tooquickly, the patient management module may issue a warning to thepatient. If the patient's responses indicate that there is an equipmentproblem, the patient management module may alert the operator. Alertingthe operator may be accomplished by wireless paging or by any othersuitable techniques (e.g., e-mail, console lights, buzzer, etc.).

[0122] As can be seen in FIG. 14, the first step in the flowchart 1400is the patient management module receives an indication of a problemfrom a calling module at step 1401. The patient management modulethereafter determines at step 1402 whether the problem is a patientwarning event. If it is, then the patient management module issueswarning to the patient at step 1403. In some embodiments, the patientmanagement module references a table that specifies which types ofevents are patient warning events and also the particular warningmessage to be issued to the patient. Such patient warning eventsinclude, for example, events that trigger the warnings in steps 713,715, 726, 923, 1117, and 1313, described above. The warning messages mayalso include short text messages describing the problem to the patient.The warnings may include an onscreen acknowledgment such as an “OK”button or a “Continue” button. The patient must then acknowledge thewarning in order to continue.

[0123] In some embodiments, the patient management module determineswhether the particular patient warning has been issued a predeterminednumber of times at step 1404. This may indicate that the patient ishaving the same difficulty over and over again. If it has, then thepatient management module may page the operator at step 1406. In someembodiments, the patient management module may also page the operator ifthe patient has not acknowledged the warning message within apredetermined amount of time.

[0124] Otherwise, the patient management module determines whether theproblem is an operator paging event at step 1405. If it is, then thepatient management module pages the operator at step 1406. As before,the patient management module may reference a table that specifies whichtypes of events are operator paging events and the messages to be issuedto the operator. In some embodiments, the messages may be in the form ofcode words that represent different types of problems. Examples ofevents that are operator paging events include step 610 (e.g., thetransducer is probably mounted incorrectly) and any other indication ofequipment problems. Operator paging may also occur if the hearings testis not completed within a given amount of time, or if the patientrequests help.

[0125] At step 1407, the patient management module performs additionalprocessing, such as compiling the number and types of warnings that weretriggered for the patient. This information may then be used to adjustthe hearing test for the patient as needed, either within the currenttest session, or in future test sessions for this patient. For example,if the patient is routinely slow in responding during the pure tonefrequency threshold test, the allotted amount of time for answering maybe increased for the other tests during this session, or for futuresessions.

[0126] To demonstrate the accuracy of the automated hearing test,several studies were recently conducted. In one representative study, agroup of 15 patients were tested using the traditional, manuallyadministered hearing test and also using the automated hearing test ofthe present invention. The results are summarized in Table 2 below.Briefly, 96 percent of all thresholds tested with the automated hearingtest of the present invention were within 10 dB of the manuallyadministered test. Likewise, 98 percent of all air thresholds, 91percent of all bone thresholds, and 93 percent of all speech receptionthresholds were within 10 dB of the manually administered test. As forspeech discrimination, the average difference between the automatedhearing test of the present invention and the manually administered testwas 0.8 percent. Thus, in addition to being easier, more convenient, andless expensive, studies have shown that the automated hearing test ofthe present invention is substantially as accurate as the traditional,manually administered test. TABLE 2 Results of Automated Hearing TestPure Tone and SRT Results Total Air Bone SRT Thresholds measured 255 18045 30 0 dB difference to manual (%) 45 50 29 40 0-5 dB difference tomanual (%) 85 91 69 70 0-10 dB difference to manual (%) 96 98 91 93 0-15dB difference to manual (%) 99 99 98 100 Over 15 dB difference to manual(%) 1 1 2 0

[0127] While the invention has been described with respect to a numberof specific embodiments, those skilled in the art will recognize thatthe innovative concepts described herein can be modified and varied overa wide range of applications. Accordingly, the scope of the inventionshould not be limited to any of the specific exemplary teachingsdiscussed, but is instead defined by the following claims.

What is claimed is:
 1. A computer-based, multimedia method for allowingthe patient to quickly and conveniently test his speech discriminationthreshold without a sound isolation chamber and with minimal assistancefrom an operator, comprising: selecting several word-picture groups froma pool of word-picture groups for presentation to the patient;determining an optimal intensity level and a masking level to be usedfor the presentation; presenting the word-picture groups to the patientone word-picture group at a time at the optimal intensity level and themasking level; checking whether termination conditions have been metupon receiving a response to the presentation; and generating a speechdiscrimination accuracy score based on the responses from the patient ifthe termination condition have been.
 2. The method according to claim 1,wherein the step of determining a masking level includes determining ifthere is a masking dilemma.
 3. The method according to claim 1, whereinthe step of determining an optimal intensity level includes calculatinga best performance point on a performance intensity curve.
 4. The methodaccording to claim 1, wherein the word-picture groups are randomlyselected.
 5. The method according to claim 1, wherein the terminationconditions include a predetermined percentage of correct responses basedon a minimum number of correct responses.
 6. The method according toclaim 1, wherein the termination conditions include a predeterminednumber of total responses.
 7. The method according to claim 1, whereinthe termination conditions are checked on a word-picture group byword-picture group basis.
 8. The method according to claim 1, whereinthe same picture group is used for each word.
 9. The method according toclaim 1, wherein no two words may have the same picture groups.
 10. Themethod according to claim 1, further comprising correcting the speechdiscrimination accuracy score for guessing.
 11. A computer-based,multimedia system for allowing a patient to quickly and convenientlytest his own speech discrimination threshold without a sound isolationchamber and with minimal assistance from an operator, comprising:transducers, including an air conduction transducer and a boneconduction transducer; a hearing test device capable of producing tones,speech, and masking noise connected to the transducers; a computerconnected to the hearing test device and storing an automated hearingtest thereon, the automated hearing test configured to cause thecomputer to: select several word-picture groups from a pool ofword-picture groups for presentation to the patient; determine anoptimal intensity level and a masking level to be used for thepresentation; present the word-picture groups to the patient oneword-picture group at a time at the optimal intensity level and themasking level; check whether termination conditions have been met uponreceiving a response to the presentation; and generate a speechdiscrimination accuracy score based on the responses from the patient ifthe termination condition have been.
 12. The system according to claim11, wherein the automated hearing test further causes the computer todetermine if there is a masking dilemma.
 13. The system according toclaim 11, wherein the automated hearing test causes the computer todetermine the optimal intensity level by calculating a best performancepoint on a performance intensity curve.
 14. The system according toclaim 11, wherein the automated hearing test causes the computer toselect the word-picture groups randomly.
 15. The system according toclaim 11, wherein the automated hearing test causes the computer tocheck the termination conditions by checking for a predeterminedpercentage of correct responses based on a minimum number of correctresponses.
 16. The system according to claim 11, wherein the automatedhearing test causes the computer to check the termination conditions bychecking for a predetermined number of total responses.
 17. The systemaccording to claim 11, wherein the automated hearing test causes thecomputer to check the termination conditions a word-picture group byword-picture group basis.
 18. The system according to claim 11, whereinthe automated hearing test causes the computer to use the same picturegroup for each word.
 19. The system according to claim 11, wherein notwo words may have the same picture groups.
 20. The system according toclaim 11, wherein the automated hearing test further causes the computerto correct the speech discrimination accuracy score for guessing.